NODE 46150467Re: triggerfish
hkhenson@cup.portal.comFri, 25 Jun 93 21:05:20 PDT
Brian D Williams <talon57@well.sf.ca.us> wrote (re TRIGGERFISH):
> It would be child's play for the NSA to accomplish this from
>orbit.....hmmmmm I wonder what they call it?
My guess would be that it can't be done. Just getting up in a
light aircraft with a cell phone is instructive. With every
cell site in 50 miles being about the same distance (even from
LEO) I don't think you could pick out a single conversation.
On the other hand, with enough directionality . . . . nah, the
antenna would be a monster.
Keith
NODE 8020b5c8Re: triggerfish
pat@tstc.edu (Patrick E. Hykkonen)Mon, 28 Jun 93 06:39:17 PDT
> > It would be child's play for the NSA to accomplish this from
> >orbit.....hmmmmm I wonder what they call it?
>
> On the other hand, with enough directionality . . . . nah, the
> antenna would be a monster.
Actually, no it wouldn't. A yagi antenna at 800 Mhz is not very large
at all. A 16 element at that frequency would probably be less than 5
feet long. Beans for a satellite to carry into orbit today. Of
course the problem then is the beam will provide a fairly wide "spot"
on the surface of the Earth that will still cover several cell sites.
Although come to think of it, narrowed to area to adjacent sites
you'll not have to contend with hearing two sites on the same
frequency due to coordination.
--
Pat Hykkonen, N5NPL Texas State Technical College at Waco
Internet: {pat,postmaster,root}@tstc.edu Instructional Network Services
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